Telecommunications systems include customer premise equipment (CPE), local loops connecting each customer premises to a central office or other node, the nodes providing switching and signaling for the system, and internode trunks connecting the various nodes. The customer premise equipment (CPE) includes telephones, modems for communicating data over phone lines, and computer and other devices that can directly communicate video, audio, and other data over a data link. The network nodes include traditional circuit-switched nodes that have transmission paths dedicated to specific users for the duration of a call and employ continuous, fixed bandwidth transmission and packet-switch nodes that allow dynamic bandwidths, dependent on the application. The transmission media between nodes may be wireline or wireless.
One type of wireline transmission media is optical fiber which is a thin strand of glass that is designed to carry information using pulses of light. Separate optical fibers are bundled together and encased in an outer sheath to form fiber cables. Optical fiber provides users with higher reliability, superior performance, and greater flexibility than traditional copper based systems.
Optical transmission facilities are installed in the form of synchronous optical network (SONET) rings. SONET defines a line rate hierarchy and frame format as described by the American National Standards Institute (ANSI) T1.105 and T1.106 specifications. SONET rings are typically bidirectional to provide redundant transmission paths and protection in case of a network failure. Nodes on a SONET ring provide add-drop multiplexing and digital cross connect functionality for traffic on the ring.
The simple network management protocol (SNMP) is heavily used for network management in the data communications industry. SNMP uses User Datagram Protocol (UDP) and Internet Protocol (IP) packets to communicate management information between a management station and a network node, which is not readily transportable on a SONET ring. As a result, SONET nodes cannot be remotely managed using SNMP and other protocol using IP and similar messaging because the network management stations do not have the ability to communicate with nodes beyond an immediately connected node. Thus, the network management station has no knowledge of the existence of any other nodes on the SONET ring outside the immediate node. To communicate with multiple nodes on the SONET ring, additional management network external to the ring must be used which is costly to implement and maintain.